The study aimed to evaluate the growth performance of three Nigerian sheep as influenced by sex and breed. A total of eighteen (18) growing (12 – 18 months) sheep comprising three rams and three ewes each of Balami, Uda and Yankasa breed were purchased from National Veterinary Research Institute (NVRI) Vom. The experimental sheep were balanced for weight and allotted into six treatments based on breed (Balami, Uda and Yankasa) and sex (rams and ewes) effects with three replicates in a 2×3 factorial arrangement. The sheep were fed a total mixed ration comprised of 14.77% crude protein for 90 days. The results indicated a significant (P<0.05) effect of sex and breed on the sheep’s weight gain and voluntary feed intake. The rams had higher (P<0.05) weight gain and feed intake than the ewes while among the three breeds, Balami recorded the highest (P<0.05) weight gain and feed intake, followed by Uda while Yankasa had the least weight gain and feed intake, although, the efficiency of feed utilization was neither affected by sex nor by breed effect. In conclusion, rams and Balami breed of sheep exhibited improved weight gain compared to ewes and Uda and Yankasa sheep. It can be recommended that for optimal growth performance rams and Balami breed of sheep should be used.